In a well servicing or production environment, it is often desirable to provide various services within a well. For example, it may be beneficial to heat some or all of the well string or a portion of the formation in which the well is drilled, in order to facilitate oil or other mineral extraction, to prevent the precipitation or hardening of drilling byproducts, or for other purposes. Or it may be desired to provide sensors or other devices downhole, and to provide electrical power required to operate the devices. In some applications, fluids may be introduced downhole. Well services may be provided by the use of an umbilical. An umbilical is an elongate line or tube that carries electrical power, fluid, control signals, or other services or combinations of services.